As developmental planning for Project Mercury evolved, NASA notified the Army that to reduce the variety of launching vehicles to Jupiter missile would not be used for Project Mercury tests.
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Controversial Operation Dominic succeeded, after two previous attempts in June, in exploding a megaton-plus hydrogen device at more than 200-mile altitude over Johnston Island in the Pacific. Carried aloft by a Thor rocket and synchronized with the approach of a TRAAC satellite, this highest thermonuclear blast ever achieved was designed to test the influence of such an explosion on the Van Allen radiation belts. The sky above the Pacific Ocean from Wake Island to New Zealand was illuminated by the blast. Later observations by probes and satellites showed another artificial radiation belt to have been created by this series of nuclear tests.
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The Molniya 8K78L was designed by Korolev's design bureau for launching a manned spacecraft on a flyby of the Moon and return to earth. To achieve this it would have used Lox/LH2 engines in the third and fourth stages. Such technology was years away in the Soviet Union and the project was not pursued further.

The launch was from one of the three active R-7 class pads at Plesetsk (LC16/pad 2, LC43/pad 3, LC43/pad 4) and used the 8K78M launch vehicle, consisting of the 11S59 core packet, the 11S510 Block I third stage, and the Block-ML upper stage. The Block ML and the payload were placed in a 62.8 degree low parking orbit and then the ML fired to deliver the payload to a 12-hour operational orbit. This was the 52nd Molniya-3 to be launched.